Proposed here is collection of the first population proportional estimates of drug abuse problems and treatment experiences. The data will be collected in 1985 for the population aged 20-27, as part of the National Labor Survey-Youth Cohort, Round 7--a panel survey conducted annually since 1979. Based on this nationally representative panel--which includes females as well as males, unemployed and employed, minority groups and whites, poor and non poor, treated and non treated--questions concerning drug problems, barriers to treatment, and experiences in treatment will be asked--in addition to information about employment, education, military experience, marriage and parenting, attitudes and background which is collected annually. These data provide the basis for five studies, descriptive and causal, which have been designed to test ethno-gender differences and to serve both policy and theoretical interests: 1) Prevalence of problems from alcohol and/or drug use; (2) Prevalence of treatment experiences--number, type, causative substances, etc., (3) Prevalence of unmet needs for treatment; (4) Test of availability-proneness theory to explain treatment entry, where dependent variable (treatment entry) as well as predictor conditions have been formulated as annually changing phenomena, not as single lifetime conditions; (5) Outcomes of drug treatment, designed to take into account normative variations by ethnicity and gender on outcome criteria such as employment, while controlling for variations in patterns of drug use, drug problems, social roles and contextual factors.